Please check the temperature of extruder reach 180°C or above, for melting the filament;
Please check the nozzle is blocked or not, if yes, please clean up the nozzle;
Please check the part assembly is correct or not, as the following image:
When the temperature of extruder reach above 210 degrees Celsius, the extruder motor can work;
When print the fifth layer, the turbo fan can work, as the setting of Cura image, pls check, thank you.